On January 13, 2021, a Piper PA-46-350P Jetprop DLX (registration ZS-JJJ) was involved in an aviation accident near On a gravel road 500m from the take-off from Koedoesberg Game Farm, ZA. Investigators recorded the probable cause as: The primary cause of the accident was an in-flight loss of engine power, which led to an unsuccessful forced landing. This power loss was driven by an air leak at the P3 air-filter housing caused by improperly torqued B-nuts. This summary draws on records from the South African Civil Aviation Authority (SACAA) Accident and Incident Investigations Division.
A Piper PA-46-350P Jetprop DLX experienced an engine power loss shortly after takeoff, resulting in a forced landing on a gravel road and serious injuries to the pilot.
What happened
On 13 January 2021, a Piper PA-46-350P Jetprop DLX, registration ZS-JJJ, departed from the Koedoesberg Game Farm private airstrip in KwaZulu-Natal. The pilot was conducting a private flight intended to practice instrument flight approaches at Pongola Aerodrome to prepare for a license renewal. Shortly after takeoff, the aircraft suffered a loss of engine power. The pilot attempted an emergency forced landing on a narrow gravel road located approximately 500 meters from the runway threshold. During the impact, the aircraft's undercarriage collapsed, and the propeller blades struck the ground before the aircraft came to rest on its fuselage. The pilot sustained serious injuries during the event.
The investigation
An investigation by the SACAA AIID examined the aircraft's maintenance history and mechanical condition. Records indicated that the aircraft had experienced similar power reduction issues on previous flights in December 2020. Although an aircraft maintenance organization had performed checks and recommended that the fuel control unit (FCU) be sent for bench testing, the aircraft was flown again prior to this resolution. Investigators examined the engine and discovered that two B-nuts on the P3 air-filter housing were not properly torqued. A leak test confirmed that these loose nuts caused an air leak in the P3 line, which supplies air to the fuel control unit. Additionally, investigators found evidence of fuel contamination in the right-wing tank and noted that the pilot had not maintained required flight folio records or fuel logs.
Probable cause
The primary cause of the accident was an in-flight loss of engine power, which led to an unsuccessful forced landing. This power loss was driven by an air leak at the P3 air-filter housing caused by improperly torqued B-nuts.